I have used the BT control tool to control Lego Mindstorm robots. It is fairly simple, as BTcontrol makes it possible to generate PC keyboard keypresses. I adapted one of the available public domain Lego Control tools, so it accepts keypresses...
The current developer of Bricx (John Binder) http://bricxcc.sourceforge.net was so kind to introduce my adaptation into the standard release from 3.3.7.2, so if you want to control your Lego robots from a phone ... fetch Bricx.
Brixc is provided with a 'Joystick' tool (under menu 'Tools'), it makes it possible to directly manipulate motors connected to your Mindstorms brick or the ones in the Cybermaster block. There are normally three ways to execute this control:
- Through a Joystick
- With the mouse clicking on the arrows
- With the numpad keys (on the right of most keyboards)
From release 3.3.7.2 of Bricx a fourth method is available, the use of the normal digit keys 1..9. Digits 1-4 and 6-9 are direction-actions and 5 stops the last action. See the picture below.
You can build a BT control menu that maps the buttons 1-9 on the phone to the direction arrows. If you follow the physical phone button location it goes like this: button 1,2 end 3 should correspond to 7,8 and 9 on the keyboard. The phone buttons 4,5 and 6 map to 4,5 and 6 of the keyboard, and then finally 7, 8 and 9 on the phone to 1,2 and 3 of the keyboard.
One the phone it looks then something like above. Then build yourself a robot and drive it around, note that you'll have some delay between a phone button press and the actual reaction of your robot..... I have an mpeg movie that shows an example using Lego Cybermaster download (rightclick to save to your computer 1200kByte) here.
With some tricking, using three motors and a rotation sensors, I quickly hacked a useful 'put-sugar-in-coffe-and-stir' robot together.
Some more pictures here , as well as the 'put-sugar-in-coffee-and-stir' in action movie.